Martindale TEK404 Continuity Tester

The Martindale TEK404 is a low cost, easy to use continuity tester.
It has audible and visual indication plus overvoltage protection and has the same loud buzzer as the TEK402, giving it a very clear signal of continuity.
With all the benefits of the TEK402 this unit adds visual indication by an LED.
The TEK404 also has safety protection in case the unit is accidentally used on live circuits.